Arrangement and method for determining the position of a unit in an electrophotographic printer or copier

Abstract

In an arrangement and method for determining a position of a unit in an electrophotographic printer or copier, a sensor arrangement is provided having two sensors and an actuating element. Each sensor outputs a sensor signal dependent on a position of the actuating element, the position of the actuating element with respect to the sensors changing dependent on a position of the unit. In a first position of the unit, the actuating element is positioned such that the first sensor and the second sensor each output a first sensor signal. In a second position of the unit the actuating element is positioned such that the first sensor outputs a second sensor signal and the second sensor outputs the first sensor signal. In a third position of the unit the actuating element is positioned such that the first sensor and the second sensor each output the second sensor signal. In a fourth position of the unit the actuating element is positioned such that the first sensor outputs the first sensor signal and the second sensor outputs the second sensor signal.

1. An arrangement for determining a position of a unit in an electrophotographic printer or copier, comprising:
 a sensor arrangement comprising two sensors and an actuating element, each sensor outputting a sensor signal dependent on a position of the actuating element, the position of the actuating element with respect to the sensors changing dependent on the position of the unit; 
 in a first position of the unit the actuating element is positioned such that the first sensor and the second sensor each output a first sensor signal, 
 in a second position of the unit the actuating element is positioned such that the first sensor outputs a second sensor signal and the second sensor outputs the first sensor signal; 
 in a third position of the unit the actuating element is positioned such that the first sensor and the second sensor each output the second sensor signal; and 
 in a fourth position of the unit the actuating element is positioned such that the first sensor outputs the first sensor signal and the second sensor outputs the second sensor signal. 
 
   
   
     2. An arrangement according to  claim 1  wherein in a fifth position of the unit the actuating element is positioned such that the first sensor and the second sensor each output a first sensor signal. 
   
   
     3. An arrangement according to  claim 1  wherein the sensors are stationarily arranged at the printer or copier. 
   
   
     4. An arrangement according to  claim 1  wherein the sensor signals comprise binary signals. 
   
   
     5. An arrangement according to  claim 1  wherein the unit can be pulled out of and pushed into the printer or copier. 
   
   
     6. An arrangement according to  claim 1  wherein the actuating element comprises a mechanical sensing element which senses a sensing area of the unit that includes different levels by which the position of the actuating element is changed when the unit is pulled out or pushed in. 
   
   
     7. An arrangement according to  claim 1  wherein the actuating element comprises a mechanical sensing element which senses a sensing area of the unit, the unit comprises a developer station, and the position of the actuating element being changed when the developer station is swung into contact with a photoconductor or when it is swung away from a photoconductor of the printer or copier. 
   
   
     8. An arrangement according to  claim 1  wherein the actuating element is formed such that it monitors a locking of the unit in a printing position of the unit. 
   
   
     9. An arrangement according to  claim 1  wherein the actuating element is formed such that it locks the unit in a printing position of the unit. 
   
   
     10. An arrangement according to  claim 1  wherein the unit comprises a developer station. 
   
   
     11. A method for determining a position of a unit in an electrophotographic printer or copier, comprising the steps of:
 providing a sensor arrangement comprising two sensors and an actuating element and outputting with each sensor a sensor signal dependent on a position of the actuating element; 
 changing a position of the actuating element with respect to the sensors dependent on a position of the unit; 
 in a first position of the unit positioning the actuating element such that the first sensor and the second sensor each output a first sensor signal, 
 in a second position of the unit positioning the actuating element such that the first sensor outputs a second sensor signal and the second sensor outputs the first sensor signal, 
 in a third position of the unit positioning the actuating element such that the first sensor and the second sensor each output the second sensor signal, and 
 in a fourth position of the unit positioning the actuating element such that the first sensor outputs the first sensor signal and the second sensor outputs the second sensor signal.